Cisplatin and Transplatin

[Tracy Tolentino_2E]

How does Cisplatin stop cell division? Why doesn't Transplatin have the same effect when forming a coordinate compound with DNA?

[sarahsalama2E]

Cisplatin has the Cl atoms on the same side while trans-diamine dichloro-platinum (ii) has them located on opposite, or diagonal sides from one another. Cisplatin is a well-known chemotherapy drug that works by forming a coordinate compound with DNA. Cisplatin binds to the exposed N in guananine and binds in 2 places so that the CL atoms are displaced through 2 bonds and the DNA replication process gets blocked. Transplatin does not work in stopping cell replication because it cannot bind to the DNA in two places because the Cl are on opposite sides and cannot bind to the exposed N in guanine.

[Robert Tran 1B]

Cisplatin stops DNA replication by bonding to two exposed guanines. This prevents the enzymes from replicating the DNA. Transplatin does not stop DNA replication because its shape only allows it to bind to one guanine. This bond is not strong enough to prevent replication.